Fatigue life and damage evaluation of Glass Fiber Reinforced Unsaturated Polyester Composite Materials Based on recycled Polyethylene terephthalate (rPET)

doi:10.21203/rs.3.rs-1967018/v1

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Fatigue life and damage evaluation of Glass Fiber Reinforced Unsaturated Polyester Composite Materials Based on recycled Polyethylene terephthalate (rPET)

https://doi.org/10.21203/rs.3.rs-1967018/v1

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Waste polyethylene terephthalate (PET) in the atmosphere creates an environmental concern. The use of waste PET as a matrix in a composite lowers the cost and environmental impact. In this study, the unsaturated polyester resin (rPET-UPR) is extracted from waste PET through the chemical recycling route (glycolysis) for the fabrication of four-ply glass fiber composites laminate of stacking sequence [0/(± 45)₂/0]_T. fatigue tests were performed at the stress ratio of 0.1, where the stress level varied from 40–80% of the ultimate tensile strength (UTS). The results of fatigue tests showed that the fatigue life of composites based on rPET-UPR was lower as compared to virgin polyester matrix composite probably due to weak interfacial properties and higher degradation of rPET-UPR matrix. Moreover rPET-UPR glass fiber composite had comparable fatigue performance. With increasing the fatigue loading cycle nonuniform and rapid damage growth were observed at high-stress levels however more uniform damage zone was observed at the low-stress level. From the fatigue fracture surface the fiber pullout, fiber pullout and fiber breakage, and fiber breakage failure mode was observed at 80%, 60%, and 45% stress level respectively while fiber pullout from intermediate ply had been observed might be due to weak interface and greater load transfer to intermediate ply after the failure of outer ply (UD). FE-SEM results revealed that excessive matrix damage was observed at low-stress level. The magnitude of stiffness degradation increased with decreasing the stress level might be due to excessive matrix damage.

Fatigue behavior

Glass fiber reinforced composite

Recycled PET

Vacuum infusion

Polyethylene terephthalate (PET) belongs to the thermoplastic polymer which has semicrystalline and is translucent in nature and also possess good mechanical properties and chemical resistance, used to make various components, mainly soft drinks and water bottles [1–4]. With an increase in the worldwide population, the utilization of PET has increased. In 2016 the demand for PET was 8400 kilotons. It is likely to increase approximately at a rate of 7% for the period of 2017–2025 [5]. The decomposition rate of PET is too slow and takes more than a hundred years to decompose in the open atmosphere in a natural manner [6, 7]. As a result of the slow decomposition rate creates an environmental problem. However, the disposal of PET in the atmosphere does not directly impact the environment. PET is nonbiodegradable and has a very high resistance to decomposition. Therefore, it seems to be a harmful material when presented in a stream [8, 9]. Recycling is one of the most appropriate routes that reduce the hazardous effect of waste PET on the environment and reduce the consumption of raw materials, cost of composite, etc., [9]. The waste PET is converted into matrix materials through chemical or mechanical recycling, and it is used for glass fiber reinforced composite materials. The composite materials based on recycled polymer matrix are well appropriated in numerous engineering applications such as aerospace, automotive, construction, etc. [10].

Carbon fiber and glass fiber are the two most commonly used synthetic fibers. Where glass fiber is cost-effective, it is used in engineering structures where the weight of composites is not more concerned and is more prone to impact loading. While carbon fiber reinforced composites are used in structure and engineering applications, where more specific strength, as well as high specific stiffness, is mandatory. Glass fiber is the most commonly used reinforcement for recycled PET. Generally, glass fiber composite with rPET matrix (thermoplastic matrix) is manufactured through mechanical recycling. In the mechanical recycling, rPET and fiber are processed through a series of heating zone of the extruder and finely produced composite by injection molding or prepared the pellets for producing the composites through compression molding. The various research group made an effort on the fabrication of glass fiber composite materials based on rPET and investigated their properties [11–13]. Cantwell [14] investigated the impact and bending strength, and fracture toughness of recycled PET glass fiber composites laminate that manufactures through compression molding and found that the recycled based composite has comparable mechanical properties to the carbon PEEK composite. Toth et al., [15] investigated the mechanical properties of rPET glass fiber composites in terms of tensile, flexural, and impact properties where rPET was mixed with epoxy acrylate and treated with radiation dosage. The test results demonstrated that the mechanical properties especially the impact strength of neet rPET and rPET-glass fiber composite were enhanced by introducing the radiation treatment and epoxy acrylate. Monti et al., [16] studied the effect of the various types of copolymer (copolymer of ethylene and methyl acrylate, ethylene and methyl acrylate, glycidyl methacrylate) on the impact strength of glass fiber reinforced rPET composite materials. It was found that the impact strength of the composite was improved with the addition of a copolymer. Volpe et al., [17] developed the glass fiber composite where a blend of virgin and recycled PET was used as a matrix and found a noticeable improvement in flexural and thermal properties when compared with rPET-based glass fiber composite.

In the fiber-reinforced composite, fiber is a major load-bearing member. Therefore, fiber content influences the mechanical properties of composites fabricated with the rPET matrix. Ronkay and Czigany [13] developed the rPET-based composite with various content of glass fiber and basalt fiber. They reported that tensile, impact, and flexural properties of the composite increased with fiber content. Kracalık et al.[18] investigated the rheological, thermal, and mechanical properties of short glass fiber reinforced rPET composite. They observed that the tensile strength, tensile modulus, flexural modulus, melt viscosity, and glass transition temperature increased with increasing fiber content. Also, Rezaeian et al.[19] observed that the tensile strength and their modulus, and impact strength of composites increased with increasing glass fiber content. A similar observation was reported by Sim et al., [20] in their experimental and numerical analysis of two different crossectional (flat and circular) specimens. The mechanical properties of composite materials depend not only on the constituent materials but also on interfacial properties or adhesion between fiber and matrix. Interfacial adhesion or interaction between glass fiber and matrix could be improved by surface modification of fiber with silane [19], epoxysilane, and aminosilane [21], leading to inflate the mechanical properties of rPET based composites. In addition, the fabrication parameters, extrusion speed [22], [23], mold temperature, and time for cooling mold [24] affect the mechanical properties rPET based glass fiber composite. Asensio et al., [25] reported that the mechanical properties of rPET based glass fiber composite was strongly related to melt viscosity. The processed with low melting viscosity had better mechanical properties. Generally, composite materials based on thermoplastics matrix are short fiber composite. Voids formation, fiber length reduction, etc., are major problems observed in the case of thermoplastics matrix (rPET) based composites. Composite materials based on thermosetting matrix processed via the hand layup or compression molding or infusion technic etc.; therefore, fiber length reduction is absent.

The unsaturated polyester resin (rPET-UPR) based on rPET is also used as a thermosetting matrix. The rPET-UPR matrix is extracted from waste PET through chemical recycling and used for producing the fiber-reinforced composites [26–29] and nanocomposites [30]. The effect of various types of nanoparticles including nano-silica [31], titanium oxide, nano clay [32], etc. on the mechanical properties of the nanocomposite. Aslan et al., [33] prepared the glass fiber reinforced rPET-UPR composite and investigated the tensile and flexural properties. The rPET-UPR based glass fiber composite has comparable mechanical properties to that of reference resin-based composite.

Over the last few decades, the glass fiber reinforced composite (GFRP) is increased in several structural applications wind turbine blades, leisure boats, space frames, etc. Polyester resin is most commonly used as a matrix to manufacture the wind turbine blade [34]. The wind turbine blade mainly consists of laminate composite that is subjected to dynamic loading. The fatigue behavior of each composite material is different. Several factors including types of constituent materials, lay-up (stacking sequences), the orientation of ply or fiber, etc. are affected the fatigue behavior of composite materials. Therefore, understanding the fatigue behavior of fiber-reinforced composite materials is need full for the development of future materials.

The available literature on glass fiber reinforced composite materials fabricated with waste PET focuses on tensile properties, flexural properties, and impact strength. There is no work has been performed to investigate the fatigue behavior of composite materials based on recycled PET [9]. This investigation explore the fatigue behavior of glass fiber reinforced composite fabricated with unsaturated polyester resin (rPET-UPR) based on recycled PET. In addition, the fatigue performance of rPET-UPR based glass fiber composite compared with the fatigue performance of virgin polyester matrix reinforced glass fiber composite [35, 36]. An organized experimental work has been carried out to accomplish the objective of this study. In addition, fatigue stiffness and hysteresis loss were monitored by measuring the load and displacement for each fatigue cycle. Also, fatigue damage in the composites was evaluated at a different fraction of fatigue cycles.

2.1 Materials and fabrication of composite

2.1.1 Preparation of matrix (rPET-UPR)

The unsaturated polyester resin (rPET-UPR) has been used as a matrix extracted from the disposed or waste PET through chemical recycling (glycolysis). The flakes of waste PET were obtained from the soft drink and water bottle. The PET flask, diethylene glycol (DEG), and zinc acetate catalyst were introduced into four necks round bottom flasks. This flask was assembled with a mechanical stirrer for mixing, reflexing condenser, thermometer, and inlet for inert gas (Fig. 1). The charged flask was heated at 210 ᴼC in a silicon oil bath. The glycolysis reaction was completed in approximately 9–10 hours. The glycolysis product, maleic anhydride, phthalic anhydride, and propylene glycol were introduced in four necks round bottom flasks assembled with a mechanical stirrer, dean stark apparatus, thermometer, and inlet for inert gas and heated at 210 ᴼC. During the reaction, a small amount of product was taken out to check the progress of the reaction by determining the acid value. During the reaction, the acid value was monitored by titration [33]. Once the acid value of the product has reached to 40–45 mg KOH/g the heating had been stopped. Obtained resin cooled to 90 ᴼC and added 0.5 wt.% of PET hydroquinone to avoid the pre-polymerization. Finally, the highly viscous resin was diluted with a styrene crosslinker.

2.1.2 Fabrication of Composite

This study used two unidirectional E-glass fibers with an areal weight of 700 g/m² and two bi-directional (± 45ᴼ) fabrics with an aerial weight of 450 g/m² and 225 g/m² to prepare the four-ply composite laminate. The prepared laminate composite was encoded as [0/(± 45)₂/0]_T. This typical stacking sequence is adopted by the wind turbine industry for rotor blade construction. The rPET-UPR resin, MEKP, and cobalt octoate accelerator were mixed and used to infuse the fabric. Rectangular laminate plates of 260 mm × 150 mm were fabricated by vacuum infusion process. Figure 2 showed the line diagram of the vacuum infusion setup. After that infused layup was kept at room condition for 24 hours to complete the curing process. The fiber content of the prepared composite with an average thickness of 2.7 mm, was calculated by the ignition loss method as per ASTM D3171-15 [37] which was found to be 48%. The tensile and fatigue test specimens were cut from the prepared laminate with a diamond cutter as per ASTM D3039/3039M-17 [38] and ASTM D3479/3479M-19 respectively [39]. Where 0º direction (longitudinal direction of UD fiber) has been considered as the reference for preparing the specimens from laminate. Testing specimens for tensile and fatigue and their dimension has been presented in Fig. 3. The edges of specimens were trimmed with silica paper of different grit sizes 600, and 1200 to abate the probabilities of failure from the edge specimens. In addition, to avoid grip failures, aluminum Tables (45× mm ×25mm ×3 mm) were glued at end of each specimen by using epoxy bond adhesive.

2.2 Testing procedures

The tensile test of prepared specimens was performed on MTS servo-hydraulic universal testing machine (capacity 250 kN). For the tensile test, the speed of crosshead was 1 mm/min. Tension-tension fatigue tests of the specimens of dimension shown in Fig. 3 were carried out according to the ASTM D3479/3479M-19 [39] at the stress ratio of 0.1. The fatigue test of all specimens was performed under the load control mode at 5 Hz frequency and six stress levels (40–80% of ultimate tensile strength, UTS). For this test, a sinosydal waveform was used. For fatigue life prediction of composites, 17 specimens were tested at six selected stress levels. At each stress level, all specimens were tested until failure or runout (10⁶ cycles). Axial load, axial displacement, and the number of cycles to failure at each stress level were recorded. The damage development in the composite during the fatigue test was evaluated with a high-resolution camera by placing the LED light source behind specimens.

3.1 FTIR spectra of prepared resin

The unsaturated polyester resin is extracted from the waste PET through the glycolysis process. A high viscous resin obtained from the reaction of glaycolyzed product reacts with phthalic anhydride, maleic anhydride, and propylene glycol and is finally diluted with styrene. Figure 4 represents the FTIR spectra of the glycolysis product. A broad absorption peak of the OH group was seen corresponding to a 3361 cm^− 1 wave number. The presence of OH group peaks was the indication of glycolysis of PET. Also, the peaks of C-H stretching corresponding to 2875 cm^− 1, C = O stretching corresponding to 1716 cm^− 1, C-O-C stretching corresponding to 1269 cm^− 1, C-OH corresponding to 1118 cm^− 1, and aromatic ester corresponding to 730 cm^− 1 was present in the FTIR spectra [40]. This indicates the glycolyzed product has ester and hydroxyl groups [41]. From the FTIR spectra of rPET-UPR, it can see the absorption peaks at 2952 cm-¹, 1637 cm-¹, 981 cm-¹, and 776 cm-¹ which was responsible for the presence of C-H stretching, C = C (polyester chain), C-H (bending) and C = C (vinyl group of styrene) respecptively [40]. The peak corresponding to 1637 cm-¹of C = C was absent in the FTIR spectra of glycolyzed product. This is provided the site for crosslinking between styrene and polyester chain [29].

3.2 Fatigue test

3.2.1 Fatigue life

The Fatigue life or S-N data were plotted on the semilogarithmic scale in terms of normalized maximum stress (σ_max/UTS) and the number of cycles to failure (N_f) as shown in Fig. 5. The fatigue behavior of composites was modeled with Basquin pawer law as follows

$${\sigma }_{max}={\sigma }_{o}{N}^{-1/k}$$

Where σ_o and 1/k are the y-intercept and slope of the S-N curve respectively. The values of these parameters were obtained by linear regression analysis of fatigue data. The obtained values of modeled parameters σ_o and 1/k were given in Table 1. From the S-N diagram (Fig. 6), it was observed that the fatigue performance in terms of fatigue life of glass fiber reinforced composite materials based on rPET-PET was less as compared to that of virgin polyester matrix glass fiber composites. The rPET-UPR based glass fiber composite had run out at the stress level of 0.4. However, virgin polyester matrix-based composite sustains more than 10⁶ load cycles at the stress level of 0.57 of their UTS. Therefore, the fatigue strength of virgin polyester matrix-based composite has comparatively higher. Also, as compared to virgin polyester matrix-based glass fiber composite, rPET-UPR based glass fiber composites have a steeper S-N curve. This indicates that the fatigue life degradation of the rPET-UPR matrix-based composite was higher as compared to virgin polyester matrix composite. Nijssen [42] reported that the composite materials of low S-N curve slope showed better fatigue behavior. Therefore, the fatigue performance of rPET-UPR based glass fiber composite was lower as compared to virgin polyester-based glass fiber composite. This was probably due to the weak interface or poor adhesion between fiber and rPET-UPR and higher degradation of the recycled matrix. All though, experimental results of fatigue demonstrated the rPET-UPR based glass fiber composite has comparable fatigue performance.

Table 1

Estimated fatigue model parameters at a stress ratio of 0.1
Composites	σ₀	1/Κ
Glass fiber-virgin polyester matrix composites	1.700	0.072
Glass fiber-rPET-UPR composites	1.754	0.1086

3.2.2 Fatigue damage analysis

Damage development in composite materials is greatly affected by the type of constituent materials, nature of loading, level of loading etc. The presence of damage in specimens reduces the transmittance of light through the specimens which resulted in dark region as illustrated in photographs. The fatigue damage development of rPET-UPR composites at the various stage of fatigue life has been represented in Fig. 6. Where dark regions represent the damage or debonds zone in the specimens of their respective number of load cycles. At the initial stage of fatigue loading, local damage was observed (Fig. 6). These local damages were initiated from the edge of the specimens which attributed to the resin deficiency or weak interface at cross overply. As increasing the load cycle crake in the matrix that developed during the initial stage of loading reaches the fiber-matrix interface as the results of this fiber debond from the matrix. Therefore, with increasing the Fatigue load cycle, the damage has been shown along the fiber in the intermediate ply and progressively increased with the fatigue load cycle. The increase of damage could be attributed to the friction between wrap and fibers. At the high-stress level, from Fig. 6a it was observed that fatigue damage in the specimens was more intense and nonuniformly growing with increasing the fatigue load cycle due to friction in the damage zone. However, at the low-stress level, the fatigue damage increased progressively and seems like a more uniform damage zone (Fig. 6b). It is clearly shown that for the same fatigue life the damage development at high-stress levels was greater as compared to low-stress level.

3.2.3 Fatigue fracture surface

Figure 7 showed the fatigue fracture specimens at 80%, 60%, and 45% stress level. From Fig. 7a it was observed that at high-stress level fiber pullout from the outer and intermediate layer. At high-stress level damage growth was rapid therefore large matrix cracking and fiber debonding were produced in the composite during the fatigue loading. Which strongly decreased the interfacial properties between fiber and matrix. This leads to decreased transfer of stress between matrix and fiber at the damage concentrated zone. As the decreasing the stress level, the damage development was seeming uniform which results in debonding of fiber being comparatively lower at the intermediate stress level consequently mixed-mode (fiber breakage and fiber pullout) failure was observed. At low-stress level damage developed at a slower rate therefore fiber pullout was absent. However, fiber pulled out had been observed from the intermediate ply at each stress level. Since the major load is contributed by the outer layer (UD). As the outer ply failed the grater load transferred to the intermediate layer. In addition, a weak interface could be also the region for fiber pullout from the intermediate ply. Figure 8 represents the later view of fracture specimens. A common failure mode delamination was observed irrespective of stress level. With decreasing the stress level the size of the delamination decreased. Figure 8a clearly showed the delamination size at 80% stress level was maximum which might be due to the large size and growth rate of fatigue cracks.

3.2.4 FE-SEM analysis of fatigue fracture surface

The fatigue fracture surface of specimens at the stress level of 80% and 45% of UTS were represented in Fig. 9. At the high-stress level, FE-SEM results revealed the (Fig. 9a) presence of matrix micro crack in the matrix and fiber debonding. The microcrack in the matrix reached to fiber-matrix interface and grow along the fiber with increasing the fatigue load cycles consequentially extensive and excessive fiber pullout was observed as shown in Fig. 9b. Moreover, the damage in the matrix was less at high-stress level (Fig. 9b). At the low-stress level fiber breakage and fiber debonding failure mode are observed as shown in Fig. 9c. In addition, large matrix damage in the form of crake have been shown (Fig. 9d). Moreover, a clean fiber surface and clean fiber pullout cavity were also observed. This indicates a weak fiber-matrix interface.

3.2.5 Hysteresis loops, total dissipation energy, and Stiffness degradation

During fatigue loading, cyclic stress-strain is developed in the composite materials. This constitutes a loop called the hysteresis loop. Hysteresis loops at different percentages of fatigue life at high-stress levels (80% of UTS) and low-stress levels (45% of UTS) have been presented in Fig. 10. The hysteresis loop shifted from the initial position due to the plastic deformation or permanent deformation. Figure 11 showed the variation of average cyclic strain versus normalized fatigue life at various stress levels. From Fig. 11 cyclic strain curve has three phases. Up to 2–8% of fatigue life rapid increase in cyclic strain was observed which was might be due to matrix cracking. However, in the second phase cyclic strain increase with steady-state up to 98% of fatigue life which was mainly attributed to debonding of fiber from the matrix. A rapid increment in cyclic strain was observed in the third phase. All though, all specimens tested at different stress levels have a similar trend. At high-stress level, the cyclic strain increased with the fatigue load cycle was comparatively higher which might be due to viscoelastic deformation of the matrix and intense damage growth.

In addition, the area of the hysteresis loop was not constant over the entire fatigue life. It was the function of stress level and the number of the fatigue load cycle. The variation of the hysteresis loop area with normalized fatigue life of selected specimens was plotted in Fig. 12. The area of hysteresis loop increased with increasing the fatigue load cycle due to the friction between the fiber-matrix or matrix-matrix interface in the damage zone. Meneghetti et al., [43] and Movahedi-Rad et al., [44] also reported that the hysteresis loop area increased with increasing the fatigue load cycle. The hysteresis loop area was increased largely after the 98% of fatigue life. This was might be due to the merging of debonding sites resulting in delamination. It was noticed that at a low-stress level, the hysteresis loop area was less as compared to that of the hysteresis loop area at a high-stress level due to longer fatigue life.

The area enclosed by the hysteresis loop shows the energy dissipation during fatigue loading. The sum of individual hysteresis loop areas is termed total dissipation energy (TDE). Figure 13 represent the TDE variation with fatigue life at various stress level. From Fig. 13 it was observed that the TDE increased with increasing the fatigue load cycle. The increase of TDE with the fatigue load cycle was due to friction in the unbound region. The specimens at low-stress levels sustain the more fatigue load cycle and consequently dissipated the more TDE during their fatigue life [43, 45].

The fatigue stiffness of composite materials is measured by the slop of the hysteresis loop. Figure 14 represents the normalized fatigue stiffness (E_n /E₁) and normalized fatigue life (N_n/N_f) where E₁ and E_n are the slop of the hysteresis loop of the first cycle and n^th cycle respectively, similarly, N_n and N_f are the fatigue life of N^th cycle and at failure respectively. From Fig. 14 it was seen that the stiffness degradation curve has three phases. In the first phase up to 2–8 percent of fatigue life, the stiffness of composite rapidly dropped due to damage (crack) initiation in the matrix [46]. However, in the second phase up to 98% fatigue life stiffness degradation increased slowly with approximately at a constant rate. The increase of stiffness degradation in this phase is due to the increase of debonding of fiber from the matrix as the crake reached the fiber-matrix interface which leads to delamination [46, 47]. While the large reduction in fatigue stiffness was observed in the third phase due to catastrophic failure of specimens as the result of fiber breakage. Similar observations were reported by [46, 48]. From the Fig. 14, it is clear that the stiffness degradation of rPET-based composites has a similar trend at a stress level of 0.8, 0.6, and 0.45. In addition, the fatigue stiffness and fatigue failure stiffness decreased with the decreasing fatigue stress level. This was might be due to the large damage accumulation and excessive matrix damage (as shown in Fig. 9d). The drop of fatigue stiffness at failure at a stress level of 0.8, 0.6, and 0.45 were 20.48%, 28.99%, and 35.19% respectively.

The unsaturated polyester resin (rPET-UPR) is extracted from the waste PET through the chemical recycling process (glycolysis) and used for composite fabrication. The experimental fatigue life and damage development of glass fiber reinforced composite materials based on rPET-UPR were investigated at a stress ratio of 0.1. For the damage evaluation, the light transmittance technic was used. The following conclusion has been drawn from the experimental results.

The rPET-UPR-based glass fiber composites have lower fatigue life and fatigue strength as compared to that of virgin polyester matrix-based composites probably due to weak interfacial properties or poor adhesion between glass fiber and rPET-UPR matrix and higher degradation of rPET-UPR. However, the rPET-UPR glass fiber composite had comparable fatigue performance.
Initially, a localized damage zone was observed at high-stress levels and low-stress levels. With increasing the fatigue loading cycle nonuniform and rapid damage growth were observed at high-stress levels however more uniform damage zone was observed at the low-stress level.
At the high-stress level, fiber pullout failure was observed mainly due to nonuniform intense damage growth. Uniformity of damage increased and decreased the damage growth with decreasing the stress level. Due to this fiber pullout and fiber breakage failure mode were observed at intermediate stress level. However, at the low-stress level the failure mode was fiber breakage. While a common failure mode fiber pullout from intermediate ply was observed irrespective of stress level. This might be due to a weak interface and greater load transferred to the intermediate ply after the failure of the outer ply (UD).
FE-SEM results demonstrated that as compared to high-stress level, more matrix damage was observed at the low-stress level.
For the same fatigue life, the rate of stiffness degradation at the high-stress level was higher as compared to the low-stress level. This was due to the rapid growth of local damage. However, the degradation of fatigue stiffness at low-stress levels was more than that at the high-stress level. Which was attributed to the large capacity to sustain the damage. The drop of fatigue stiffness at failure at a stress level of 80%, 60%, and 45% were 20.48%, 28.99%, and 35.19% respectively.
The hysteresis loop area was the function of the level of fatigue load level and fatigue load cycle. As increasing the stress level and fatigue loading cycle, the hysteresis loop area was increased due to the internal friction debonding zone.
The cyclic strain at a high-stress level was higher as compared to low-stress level which might be due to viscoelastic deformation of the matrix and intense damage growth.

Acknowledgment

The author wishes to express his deep graduate to the department of mechanical engineering of Dr. B R Ambedkar National Institute of Technology Jalandhar for their support and encouragement. The author also thanks my co-author for their support, sincere guidance, and contribution to this article.

Data Availability Statement

This manuscript has no associated data.

Funding

There is no specific funding for the research work presented in this paper.

Authers Contribution

Ashwani Kumar Singh: Conceptualization, Methodology, Sample preparation, Experimentation, Visualization, Validation, data curation, Formal analysis, Writing—Original Draft.

Raman Bedi: Supervision, Conceptualization, Resources, Formal analysis, Writing—review and editing.

Conflict of interest

No potential conflict of interest is reported by the author(s)

Karayannidis GP, Achilias DS, Sideridou ID, Bikiaris DN (2005) Alkyd resins derived from glycolized waste poly(ethylene terephthalate). Eur Polym J 41:201–210. https://doi.org/10.1016/j.eurpolymj.2004.10.001
Singh AK, Bedi R, Kaith BS (2020) Mechanical properties of composite materials based on waste plastic - a review. Mater Today Proc 26:1293–1301. https://doi.org/10.1016/j.matpr.2020.02.258
Thabah W, Kumar Singh A, Bedi R (2021) Tensile properties of urea treated rice straw reinforced recycled polyethylene terephthalate composite materials. Mater Today Proc. https://doi.org/10.1016/j.matpr.2021.11.464
Chen RS, Ahmad S, Gan S (2017) Characterization of recycled thermoplastics-based nanocomposites: Polymer-clay compatibility, blending procedure, processing condition, and clay content effects. Compos Part B Eng 131:91–99. https://doi.org/10.1016/j.compositesb.2017.07.057
Velásquez EJ, Garrido L, Guarda A, et al (2019) Increasing the incorporation of recycled PET on polymeric blends through the reinforcement with commercial nanoclays. Appl Clay Sci 180:105185. https://doi.org/10.1016/j.clay.2019.105185
Khoonkari M, Haghighi AH, Sefidbakht Y, et al (2015) Chemical Recycling of PET Wastes with Different Catalysts. Int J Polym Sci 2015:. https://doi.org/10.1155/2015/124524
Liu X, Wen Y, Chen X, et al (2020) Co-etching effect to convert waste polyethylene terephthalate into hierarchical porous carbon toward excellent capacitive energy storage. Sci Total Environ 723:138055. https://doi.org/10.1016/j.scitotenv.2020.138055
Paszun D, Spychaj T (1997) Chemical Recycling of Poly(ethylene terephthalate). Ind Eng Chem Res 36:1373–1383. https://doi.org/10.1021/ie960563c
Singh AK, Bedi R, Kaith BS (2021) Composite materials based on recycled polyethylene terephthalate and their properties – A comprehensive review. Compos Part B 219:108928. https://doi.org/10.1016/j.compositesb.2021.108928
Abdelhaleem AMM, Megahed M, Saber D (2018) Fatigue behavior of pure polypropylene and recycled polypropylene reinforced with short glass fiber. J Compos Mater 52:1633–1640. https://doi.org/10.1177/0021998317729888
Novello MV, Carreira LG, Canto LB (2014) Post-consumer polyethylene terephthalate and polyamide 66 blends and corresponding short glass fiber reinforced composites. Mater Res 17:1285–1294. https://doi.org/10.1590/1516-1439.281914
Pegoretti A, Penati A (2004) Recycled poly(ethylene terephthalate) and its short glass fibres composites: Effects of hygrothermal aging on the thermo-mechanical behaviour. Polymer (Guildf) 45:7995–8004. https://doi.org/10.1016/j.polymer.2004.09.034
F. Ronkay and T. Czigany (2006) Development of composites with recycled PET matrix. Polym Adv Technol 17:830–834. https://doi.org/10.1002/pat.750
Cantwell WJ (1999) Fracture behavior of glass fiber/recycled PET composites. J Reinf Plast Compos 18:373–387. https://doi.org/10.1177/073168449901800406
Tóth K, Czvikovszky T, Abd-Elhamid M (2004) Radiation-assisted PET recycling using glass fiber reinforcement and reactive additives. Radiat Phys Chem 69:143–147. https://doi.org/10.1016/S0969-806X(03)00447-X
Monti M, Scrivani MT, Kociolek I, et al (2021) Enhanced impact strength of recycled PET/glass fiber composites. Polymers (Basel) 13:1471. https://doi.org/10.3390/polym13091471
Volpe V, Lanzillo MS, Molaro A, et al (2022) Characterization of Recycled/Virgin Polyethylene Terephthalate Composite Reinforced with Glass Fiber for Automotive Applications. J Compos Sci 6:59. https://doi.org/10.3390/jcs6020059
Kracalık M, Pospısil L, Slouf M, et al (2008) Effect of Glass Fibers on Rheology, Thermal and Mechanical Properties of Recycled PET. Polym Compos 29:915–921. https://doi.org/10.1002/pc.20467
Rezaeian I, Jafari SH, Zahedi P, Nouri S (2009) An Investigation on the Rheology, Morphology, Thermal and Mechanical Properties of Recycled Poly (ethylene terephthalate) Reinforced With Modified Short Glass fibers. Polym Compos 30:993–999. https://doi.org/10.1002/pc
Sim J, Yu S-H, Yoon H-S, et al (2021) Characteristic evaluation and finite element analysis of glass fiber/recycled polyester thermoplastic composites by cross-sectional shape of glass fiber. Compos Part B Eng 223:109095. https://doi.org/10.1016/j.compositesb.2021.109095
Mondadori NML, Nunes RCR, Canto LB, Zattera AJ (2012) Composites of recycled PET reinforced with short glass fiber. J Thermoplast Compos Mater 25:747–764. https://doi.org/10.1177/0892705711412816
Giraldi ALFDM, Jesus RC De, Mei LHI (2005) The influence of extrusion variables on the interfacial adhesion and mechanical properties of recycled PET composites. J Mater Process Technol 162–163:90–95. https://doi.org/10.1016/j.jmatprotec.2005.02.046
Giraldi ALFDM, Bartoli JR, Velasco JI, Mei LHI (2005) Glass fibre recycled poly(ethylene terephthalate) composites: Mechanical and thermal properties. Polym Test 24:507–512. https://doi.org/10.1016/j.polymertesting.2004.11.011
Mondadori NML, Nunes RCR, Zattera AJ, et al (2008) Relationship between Processing Method and Microstructural and Mechanical Properties of Poly(ethylene terephthalate)/Short Glass Fiber Composites. J Appl Polym Sci 109:3266–3274. https://doi.org/10.1002/app.28459
Asensio M, Esfandiari P, Núñez K, et al (2020) Processing of pre-impregnated thermoplastic towpreg reinforced by continuous glass fibre and recycled PET by pultrusion. Compos Part B Eng 200:. https://doi.org/10.1016/j.compositesb.2020.108365
I. Ahmad, Z. Mosadeghzad, R. Daik AR (2008) The Effect of Alkali Treatment and Filler Size on the Properties of Sawdust/UPR Composites Based on Recycled PET Wastes. J Appl Polym Sci 116:3651–3658. https://doi.org/10.1002/app28488
Abdullah NM, Ahmad I (2013) Potential of using polyester reinforced coconut fiber composites derived from recycling polyethylene terephthalate (PET) waste. Fibers Polym 14:584–590. https://doi.org/10.1007/s12221-013-0584-7
Farahani GN, Ahmad I, Mosadeghzad Z (2012) Effect of Fiber Content, Fiber Length and Alkali Treatment on Properties of Kenaf Fiber/UPR Composites Based on Recycled PET Wastes. Polym - Plast Technol Eng 51:634–639. https://doi.org/10.1080/03602559.2012.659314
Tan C, Ahmad I, Heng M (2011) Characterization of polyester composites from recycled polyethylene terephthalate reinforced with empty fruit bunch fibers. Mater Des 32:4493–4501. https://doi.org/10.1016/j.matdes.2011.03.037
Asaad JN, Abd-El-Messieh SL, Ikladious NE (2014) Unsaturated polyester nanocomposites based on poly(ethylene terephthalate) waste using different types of nanofillers. Proc Inst Mech Eng Part N J Nanoeng Nanosyst 228:174–183. https://doi.org/10.1177/1740349913508106
Rusmirović JD, Trifković KT, Bugarski B, et al (2016) High performance unsaturated polyester based nanocomposites: Effect of vinyl modified nanosilica on mechanical properties. Express Polym Lett 10:139–159. https://doi.org/10.3144/expresspolymlett.2016.14
Marinkovic AD, Radoman T, Dzunuzovic E, et al (2013) Mechanical properties of composites based on unsaturated polyester resins obtained by chemical recycling of poly(ethylene terephthalate). Hem Ind Ind 67:913–922. https://doi.org/10.2298/hemind130930077m
Aslan S, Immirzi B, Laurienzo P, et al (1997) Unsaturated polyester resins from glycolysed waste polyethyleneterephthalate: Synthesis and comparison of properties and performance with virgin resin. J Mater Sci 32:2329–2336. https://doi.org/10.1023/A:1018584519173
Mousavi Khorasani MA, sahebian samaneh, Zabett A (2021) Effects of toughened polyester on fatigue behavior of glass fiber reinforced polyester composite for wind turbine blade. Polym Compos 42:70–82. https://doi.org/10.1002/pc.25808
Philippidis TP, Vassilopoulos AP (2002) Complex stress state effect on fatigue life of GRP laminates. Part I, Experimental. Int J Fatigue 24:813–823. https://doi.org/10.1016/S0142-1123(02)00003-8
Vassilopoulos AP, Keller Thomas (2011) Fatigue of Fiber reiforced Composites. Springer Science & Business Media
ASTM International (2015) ASTM D3171-15 Standard Test Methods for Constituent Content of Composite Materials. West Conshohocken, PA; ASTM Int. https://doi.org/10.1520/D3171-15
ASTM International (2017) ASTM D3039/D3039M Standard Test Method for Tensile Properties of Polymer Matrix Composite Materials. West Conshohocken, PA; ASTM Int. https://doi.org/10.1520/D3039_D3039M-17
ASTM International (2019) ASTM D3479/D3479M-19 Standard Test Method for Tension-Tension Fatigue of Polymer Matrix Composite Materials. West Conshohocken, PA ASTM Int. https://doi.org/10.1520/D3479_D3479M-19
Bakar RDA, Ahmad I, Ramli A (2006) Chemical Recycling of PET Waste from Soft Drink Bottles to Produce a Thermosetting Polyester Resin. Malaysian J Chem 8:22–26
Potiyaraj P, Klubdee K, Limpiti T (2007) Physical properties of unsaturated polyester resin from glycolyzed PET fabrics. J. Appl. Polym. Sci. 104:2536–2541
Nijssen RPL (2006) Fatigue life prediction and strength degradation of wind turbine reactor blade composites. Contractor Report SAND2006-7810P, Sandia National Laboratories, Albuquerque, NM
Meneghetti G, Ricotta M, Lucchetta G, Carmignato S (2014) An hysteresis energy-based synthesis of fully reversed axial fatigue behaviour of different polypropylene composites. Compos Part B Eng 65:17–25. https://doi.org/10.1016/j.compositesb.2014.01.027
Movahedi-Rad AV, Keller T, Vassilopoulos AP (2018) Fatigue damage in angle-ply GFRP laminates under tension-tension fatigue. Int J Fatigue 109:60–69. https://doi.org/10.1016/j.ijfatigue.2017.12.015
Singh KK, Ansari MTA, Azam MS (2021) Fatigue life and damage evolution in woven GFRP angle ply laminates. Int J Fatigue 142:105964. https://doi.org/10.1016/j.ijfatigue.2020.105964
Koricho EG, Belingardi G, Beyene AT (2014) Bending fatigue behavior of twill fabric E-glass/epoxy composite. Compos Struct 111:169–178. https://doi.org/10.1016/j.compstruct.2013.12.032
Peng T, Liu Y, Saxena A, Goebel K (2015) In-situ fatigue life prognosis for composite laminates based on stiffness degradation. Compos Struct 132:155–165. https://doi.org/10.1016/j.compstruct.2015.05.006
Padmaraj NH, Vijaya KM, Dayananda P (2021) Experimental investigation on fatigue behaviour of glass/epoxy quasi-isotropic laminate composites under different ageing conditions. Int J Fatigue 143:105992. https://doi.org/10.1016/j.ijfatigue.2020.105992

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Fatigue life and damage evaluation of Glass Fiber Reinforced Unsaturated Polyester Composite Materials Based on recycled Polyethylene terephthalate (rPET)

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Abstract

Figures

1 Introduction

2 Fabrication Of Composites And Experimentation

2.1 Materials and fabrication of composite

2.1.1 Preparation of matrix (rPET-UPR)

2.1.2 Fabrication of Composite

2.2 Testing procedures

3 Result And Discussion

3.1 FTIR spectra of prepared resin

3.2 Fatigue test

3.2.1 Fatigue life

3.2.2 Fatigue damage analysis

3.2.3 Fatigue fracture surface

3.2.4 FE-SEM analysis of fatigue fracture surface

3.2.5 Hysteresis loops, total dissipation energy, and Stiffness degradation

4 Conclusions

Declarations

References

Additional Declarations

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